Agronomic performance and water‐soluble carbohydrate expression of selected ryegrasses at two locations in New Zealand

Agronomic trials at cool (Gore) and warm (Palmerston North) temperate sites in New Zealand tested ten United Kingdom‐bred (six diploids, four tetraploids) and two New Zealand‐bred diploid (‘Bronsyn’, ‘Impact’) perennial and long‐term hybrid ryegrasses ( Lolium perenne, L. boucheanum ) over two trial periods. Dry matter (DM) yields and persistence were better at the cool site but differential expression among cultivars for water‐soluble carbohydrates (WSC) and yields was small compared with the warm site. The tetraploid cultivars generally had the highest concentrations of WSC but also on occasions had higher levels of crown rust, moderate DM yields and poorer persistence compared with diploids. Two of the tetraploid cultivars will be of value for their high WSC and good agronomic performance at the cool site. Some of the diploid UK cultivars expressed higher WSC and had similar or higher annual DM yields than some of the NZ‐bred cultivars, and had high levels of resistance to crown rust. Overall, differences among cultivars in expression of WSC were small. Some differences occurred for seasonal DM yields with some UK cultivars having lower winter yields.